ProSoundWeb Community
Sound Reinforcement  Forums for Live Sound Professionals  Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => LAB Subwoofer Forum => Topic started by: Ted Christensen on March 01, 2012, 09:43:01 pm

I own a few of these and power two a side with a 5000i stereo. Was wondering what everyone else was using to power there danleys.
Thanks!

I own a few of these and power two a side with a 5000i stereo. Was wondering what everyone else was using to power there danleys.
Thanks!
Which impedance cabinet do you have. The origional ones were 8 ohm. After a couple of years the standard impedance was changed to 4 ohmdue to people having a hard time providing a large enough amp for them. 8 ohm is still availablebut the standard is 4 ohm.
The impedance will affect how you power themto get the most out of themas with any loudspeaker.

I see a lot of posters on here tend to use an iTech8k for a pair. No personal experience though.

I use IT8Ks to power 4 of the 8ohm Th115s
I see a lot of posters on here tend to use an iTech8k for a pair. No personal experience though.

Thanks Hal and everyone else. I have the 8ohm version.
How do you like the 8ks for the sub? It doesn't seem that much different than my 5000i. Maybe a few more watts but the db level wouldn't be noticeble. Correct?

If you can afford it I am getting good results powering my eight ohmTH115s with Lab Gruppen FP+14,000 and it’s more expensive brother PLM 14,000 with good results.
Two boxes per channel. When we are stretched thin I sometimes do three boxes per channel, they seem to roar even louder this way.
Franz

I own a few of these and power two a side with a 5000i stereo. Was wondering what everyone else was using to power there danleys.
Thanks!
xti6000 powers one 4 ohm TH115 a side. For my uses it provides enough gut, but I rarely use them cranked up and outdoors  would like to hear them ripping, powered by an ITech 8000.

I own a few of these and power two a side with a 5000i stereo. Was wondering what everyone else was using to power there danleys.
Thanks!
+1 on the ITech 8k and TH115 combo. I've been running 4 (8ohm)115s + an ITech 8k for several years and love the performance.

I've looked at the specs on the 4ohm version and they are 106db vs 101db at 8ohms for sensitivity. So at 5db more a box roughly..assuming specs are accurate that's almost 30dB extra in sub output. Correct?
Should we be switching to 4 ohm drivers?

I've looked at the specs on the 4ohm version and they are 106db vs 101db at 8ohms for sensitivity. So at 5db more a box roughly..assuming specs are accurate that's almost 30dB extra in sub output. Correct?
Should we be switching to 4 ohm drivers?
Incorrect, and no.
Danley speakers use a standard voltage as a reference for sensitivity. That means the 4Ω version is getting twice as much power as the 8Ω version at that standard voltage. If your amps can deliver double the power into half the impedance you are using now, you will get the benefit of the higher power levels.
A 5dB increase per box in a 6 box array does not mean a 30dB increase for the array. It is just a 5dB increase.
Mac

Incorrect, and no.
Danley speakers use a standard voltage as a reference for sensitivity. That means the 4Ω version is getting twice as much power as the 8Ω version at that standard voltage. If your amps can deliver double the power into half the impedance you are using now, you will get the benefit of the higher power levels.
A 5dB increase per box in a 6 box array does not mean a 30dB increase for the array. It is just a 5dB increase.
Mac
And to add to this: the 4 ohm (version of this woofer) is not just half the impedance of the 8 but instead is somewhere between 4 and 8. If u compare the spec sheets from Danley you can see that the minimum impedance of the newer version is 5 ohms! Maybe it should be called a 6 ohm box instead of 4. Further, the functional parameters of the woofers are slightly different as well so there are some slight differences in frequency response. But, the overall broadband output potential of each version should be basically the same. It's just a matter of how many volts it takes to get there. BTW, I like it when amp spec sheets also list total output swing in volts. Calculating back from power ratings takes time and isn't always accurate. Knowing the rail voltages of the power supply is nice too.

And to add to this: the 4 ohm (version of this woofer) is not just half the impedance of the 8 but instead is somewhere between 4 and 8. If u compare the spec sheets from Danley you can see that the minimum impedance of the newer version is 5 ohms! Maybe it should be called a 6 ohm box instead of 4. Further, the functional parameters of the woofers are slightly different as well so there are some slight differences in frequency response. But, the overall broadband output potential of each version should be basically the same. It's just a matter of how many volts it takes to get there. BTW, I like it when amp spec sheets also list total output swing in volts. Calculating back from power ratings takes time and isn't always accurate. Knowing the rail voltages of the power supply is nice too.
EXACTLY! That is the reason Danley gives the sensitivity in voltsinstead of power.
The rating is for the closest "standard" impedance value.
Another "for example" is the SH50. Origionally it was rated as a 6 ohm cabinetwhich more closely described the load it presented to the amplifier.
However I got calls ALL THE TIME with people asking about which amp to use for a 6 ohm cabinet. They could not find 6 ohms on the spec sheets of the amps. It really confused themand when I tried to explain it, they go even more confused.
We changed the impedance rating to 4 ohms and all those phone calls stopped. It was now "simple". Since the origional specs were in input VOLTAGEthose numbers did not change. If we had used wattagebased on 6 ohmsthen the sensitivity would have also had to change with the 4 ohm rating.
That is one reason why Danley uses the voltage method of sensitivity.
The "wattage" method is also flawed in that as the freq changes the sensitivity would also have to changedue to a different "wattage" being applied to a loudspeaker because of the different impedance.
You cannot apply 1 watt (evenly across all freq) to a loudspeaker. If you didthen the freq response would be quite differentbecause at the freq that have a high impedancethe freq response would have a corrispondingly higher outputwhich is not real and not what it sounds like.
You can only apply a voltageand the wattage is calculated based on that wattage and "some" impedancepresumeably the rated impedanceeven though that impedance may or may not be an accurate description of the load presented to the amplifier.
Amplifiers DO NOT produce a wattage output. They produce a VOLTAGE output that stay constant with varying loads (assuming the amplifier is not at the current limits)so it makes more sense to rate the loudspeakers with a voltage (like the amps) rather than a wattage.